/*********************************************************************
*
* Software License Agreement (BSD License)
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* Author: Morgan Quigley
*********************************************************************/

#ifndef TWIRLING_COST_FUNCTION_H
#define TWIRLING_COST_FUNCTION_H

#include <base_local_planner/trajectory_cost_function.h>
#include <math.h>

namespace base_local_planner
{

/**
* This class provides a cost based on how much a robot "twirls" on its
* way to the goal. With differential-drive robots, there isn't a choice,
* but with holonomic or near-holonomic robots, sometimes a robot spins
* more than you'd like on its way to a goal. This class provides a way
* to assign a penalty purely to rotational velocities.
*/
class TwirlingCostFunction : public base_local_planner::TrajectoryCostFunction
{
public:

    TwirlingCostFunction() {}

    ~TwirlingCostFunction() {}

    // add cost for making the robot spin
    // 最简单的打分方式，直接输出角速度，角速度越大，输出的代价越大
    double scoreTrajectory(Trajectory &traj) { return fabs(traj.thetav_); }

    bool prepare() { return true; };
};

} /* namespace base_local_planner */
#endif /* TWIRLING_COST_FUNCTION_H_ */
